This project has 4 main lines of investigation. Firstly, we are currently undertaking a comprehensive molecular analysis of lung cancer tissues from European Americans and African Americans, including microRNA, coding gene expression, genetics and methylation. The goal of these analyses are to understand whether differences in tumor biology exist in lung cancers from African Americans and European Americans. Understanding such differences could provide clues for etiology, prevention and new treatments. In addition, a major goal of this project is to understand the biology behind genetic loci specifically associated with lung cancer incidence in African Americans. This work extends from an NCI-led GWAS of lung cancer in African Americans. Thirdly, based on previous literature suggesting that the cytokine profile is different in African Americans and European Americans, and ongoing work in European Americans showing that cytokine profiles are very promising risk, diagnostic and prognostic biomarkers, we are investigating whether a specific inflammatory cytokine profile is also associated with the diagnosis and prognosis of lung cancer in European Americans. Finally, as the disparity in lung cancer incidence between African Americans and European Americans is primarily observed among men, we are also conducting a preliminary analysis of hormonal differences in cases and controls to explore this fourth angle as a contributing factor to racial disparities.